Desperately need help with BLUE-GREEN ALGAE (CYANOBACTERIA)

[beijing08]

It's very troubling to me that my OEBT tank started developing the dreaded blue-green algae. Since it's a type of photosynthetic bacteria, I'm not sure of the most effective method to extinguish this type of "algae".

Anyone had experience with this? It would be appreciated if you could share your methods or thoughts.

[imke_j]

Hi beijing, you have too much nutrients (Nitrate, Phosphor and others) in your tank, that's why the blue-green algae (BGA) spreads. To make them go, big water changes and darkness are necessary. Here is a timeline (from Bernd Kaufmann):

1. big water change (ca. 70 %).
2. add air to the tank (air stone)
3. remove CO2 units from the tank
4. completely darken the tank for 6-7 days with cardboard or similar (no daylight)
5. no food adding if possible, very sparse when you have juvenile
6. if you have a big amount of algea, do a water change of 50% on the 3rd day
7. on day 6 or seven, turn on tank lightning again
8. on day 6 and 7 do 90 % water change each day - that is very important and necessary for the overall success!

[beijing08]

Hi beijing, you have too much nutrients (Nitrate, Phosphor and others) in your tank, that's why the blue-green algae (BGA) spreads. To make them go, big water changes and darkness are necessary. Here is a timeline (from Bernd Kaufmann):

1. big water change (ca. 70 %).
2. add air to the tank (air stone)
3. remove CO2 units from the tank
4. completely darken the tank for 6-7 days with cardboard or similar (no daylight)
5. no food adding if possible, very sparse when you have juvenile
6. if you have a big amount of algea, do a water change of 50% on the 3rd day
7. on day 6 or seven, turn on tank lightning again
8. on day 6 and 7 do 90 % water change each day - that is very important and necessary for the overall success!

this is MUCH appreciated! however, I only have a few patches of bluegreen, so it hasn't spread yet. After a 30% water change today, I scraped off most of bluegreen with a razor.
If it bounces back rapidly, I will stick to your advice. I read online that bluegreen is caused by a LACK of nitrates. Not sure if that is true or it is misleading info?

[countcoco]

A lot of people have luck using the black out method and adding charcoal to the filter. I thought I'd read that bga creates its own nitrogen source, so limiting nitrates won't solve the problem.

What is the tank like? Lighting, photoperiod, fert regime, etc?

[beijing08]

A lot of people have luck using the black out method and adding charcoal to the filter. I thought I'd read that bga creates its own nitrogen source, so limiting nitrates won't solve the problem.

What is the tank like? Lighting, photoperiod, fert regime, etc?

It's fairly simple. I've got it right beside the window. so it gets a good amount of light every day. No ferts watsoever.
Maybe a few drops of excel 3 times a week.
somehow BGA is associated with low nitrates correct?

[countcoco]

I honestly have no idea what causes bga and there seem to be a ton of different theories. However, if it were low nitrates, then every crs tank would be covered in it.

If you up the excel dosing, that will wipe it out, but it's not a good idea if you've got shrimp in there.

[Chrisjj]

I beleive nerite snails eat BGA - not a cure, but will get rid.

Is it a fairly new set up - I got it in my CRS tank after a few months - it then just disappeared on it's own?!

[beijing08]

I beleive nerite snails eat BGA - not a cure, but will get rid.

Is it a fairly new set up - I got it in my CRS tank after a few months - it then just disappeared on it's own?!

I don't think nerites will thrive in a softwater/acidic water tank. Their shells will definitely begin to disintegrate. Furthermore, YOU may have found the balance in nutrients in the water, causing the first bloom to die off.

[countcoco]

If you're looking for a good algae eater to help out, try SAEs or a garra pingi pingi.

[beijing08]

If you're looking for a good algae eater to help out, try SAEs or a garra pingi pingi.

funny name garra pingi pingi, never heard of this before.
anyhow, no SAE's in my OEBT tank hahaha. First they'll hunt little shrimplets. they'll also become the major competitor for good algae for the shrimps. I will try manual method for now, since it's only a few cm's in diameter.